A torque fluctuation absorbing apparatus is provided at an output shaft of an engine for absorbing (restraining) a torque fluctuation generated between the engine and a transmission of a vehicle as an example. Such torque fluctuation absorbing apparatus generally includes a flywheel, a limiter portion and a damper portion. The flywheel is connected to a crankshaft of the engine. The limiter portion includes a frictional member which is arranged to frictionally engage with the flywheel. The limiter portion is provided at a radially outward portion of the damper portion. A radially inward portion of the damper portion is connected to an input shaft of the transmission. The damper portion is employed for reducing the torque fluctuation inputted from the engine. Examples of a known torque fluctuation absorbing apparatus will be described below.
JP 2003-194095A (hereinafter, referred to as reference 1) discloses a torque fluctuation absorbing apparatus including a flywheel, which is fixedly connected to a driving shaft and to which a driving torque outputted from a power source is transmitted through the driving shaft, and a damper mechanism, which includes a limiter portion having a frictional member operated to directly or indirectly frictionally engage with the flywheel and which is connected to an input shaft of a transmission. According to the reference 1, the torque fluctuation absorbing apparatus further includes a supporting mechanism for fixedly connecting the damper portion to the driving shaft. More specifically, the supporting mechanism supports (interposes therein) the frictional member of the limiter portion in an axial direction of the driving shaft so that the frictional member is in a frictional engagement state before assembling the damper mechanism onto the flywheel, and the damper mechanism is then fixedly connected to the driving shaft. As another structure, the supporting mechanism supports (interposes therein) the frictional member of the limiter portion in the axial direction of the driving shaft so that the frictional member and the flywheel are directly or indirectly frictionally engaged with each other, and the damper mechanism is then fixedly connected to the driving shaft. Further according to the reference 1, the frictional member of the limiter portion is prevented exposing to an external ambience when carrying (transferring) the torque fluctuation absorbing apparatus during the assembly operation. Accordingly, a lubricant, extraneous objects (such as dust), and the like are reduced from being attached to the frictional member as far as possible.
Further, JP2002-13547A (hereinafter, referred to as reference 2) discloses a damper mechanism for a hybrid type actuating apparatus, which is employed for transmitting a driving torque generated by a first power source and/or a second power source while controlling a torque fluctuation generated therebetween. According to the reference 2, the damper mechanism for the hybrid type actuating apparatus includes a limiter mechanism, which interrupts a torque transmission when the torque fluctuation generated between the first and/or second power sources reaches a predetermined value. The damper mechanism according to the reference 2 further includes a first rotational member which is driven to rotate by the first power source, a second rotational member which is connected to the second power source, and a torsion member which controls (restrains) the torque fluctuation generated between the first and second rotational members. Specifically, the limiter mechanism interrupts a torque transmission from the first rotational member to the second rotational member when the torque fluctuation generated therebetween reaches the predetermined value. Still further, an inertial member is provided at the first and/or second rotational members. According to the reference 2, the damper mechanism controls a large torque fluctuation generated between plural power sources without increasing a size and a weight of the torque fluctuation absorbing apparatus.